Abstract
The Brazilian Code ABNT NBR 7190 (1997Associação Brasileira de Normas Técnicas. NBR-7190: Projeto de Estruturas de Madeira. Rio de Janeiro; 1997.) is currently under review process and one of the proposals is the change and add of some test procedures. Several specimen geometric configurations and test conditions have been evaluated by the study committee CE-02:126.10. The aim of this paper was the analysis of the tensile strength perpendicular to the grain through the current Brazilian Code and from an adaptation of ISO 13910 (2005International Standard. ISO-13910: Structural timber - Characteristic values of strength-graded timber - Sampling, full-size testing and evaluation. Switzerland; 2005.). Pine and Indian Cedar were used and simplified relationships were proposed. Numerical simulations were performed to identify the stress distributions in the specimens. The results obtained by ISO 13910 (2005International Standard. ISO-13910: Structural timber - Characteristic values of strength-graded timber - Sampling, full-size testing and evaluation. Switzerland; 2005.) did not differ statistically for the two species. Brazilian standard method cedar had a higher strength value than pine. The simplified ratios obtained ranged between 0,017 and 0,123. The numerical simulations of ISO 13910 (2005International Standard. ISO-13910: Structural timber - Characteristic values of strength-graded timber - Sampling, full-size testing and evaluation. Switzerland; 2005.) specimens showed predominant failure by tension in the lower fiber due to stress concentration.
Keywords:
Wood Strength; Mechanical Testing; Finite Element Method; Standardization